This invention relates generally to a device for detection of the speed of rotation of a rolling bearing which has an encoder mounted on the rotating part of the bearing and a sensor unit consisting of a sensor holder attached to a support for positioning of the sensor unit mounted in contact with the nonrotating part of the bearing.
French Patent No. 2,667,947 A describes a device in which an annular sensor holder is immobilized between the stationary ring of a rolling element and a shoulder of the positioning support. The angular displacements of the sensor holder following the stray axial movements of the rolling element in its housing induce erroneous information and premature deterioration of the electrical connections.
French Patent No. 2,693,272 A describes a device in which the metallic support of the sensor unit has a roughly axial centering seat in contact with a bearing surface arranged on the nonrotating part of the bearing. For the purpose of increasing the precision of mounting of the sensor unit, a known method is to immobilize the metallic support of the sensor unit between a nonrotating radial surface of the bearing and an adjacent radial surface. The replacement of the sensor holder requires the rolling element to be disassembled beforehand.
In such devices, the correct mounting of the sensor unit requires one to comply with a large number of manufacturing tolerances which must be even more precise as the encoder element becomes smaller and its magnetic field weaker. The annular configuration leads, during its possible disassembly, to the complete removal of the rotating assembly.
The foregoing illustrates limitations known to exist in present devices and methods. Thus, it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter.